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Crystal Malt is a subset of Caramel Malt. Thus all Crystal Malts are Caramel Malts, but not all Caramel Malts are Crystal Malts. Confusing the issue of nomenclature is the fact that Crystal Malt is sometimes referred to as Caramel Malt, especially by American maltsters. It is not possible to tell whether a "caramel malt" is Crystal Malt or a non-crystal Caramel Malt solely from the name used by the maltster.

Crystal Malt refers to green malt that is roasted in a drum roaster at around 150°F, creating steam and causing the starches to be converted to sugar inside the husk (each grain is a tiny, self-contained mash). The grains are then roasted at increasingly higher temperatures to achieve around 300°F, at which time the sugar is crystallized and caramelized within the husk. Thus, around 90% of the grains have hard, glassy crystals of sugar inside. The duration and temperature profile of the roasting determines the Lovibond color of the Crystal Malt produced this way. This is very much a handmade process, with the skill of the roaster being an integral part of the process.

(Incidentally, "green" malt means that the grains are still living and growing at the time of roasting or kilning.)

Moving on to non-crystal Caramel Malt, this malt is also produced using green malt, but it is traditionally produced in a kiln. The grains are spread in an even layer on the floor of the kiln. While the grains in the bottom layers of the kiln become crystal malts, as described above, the grains on the top layers get dried and Maillard reactions occur in the malts, creating malts that are similar to Vienna Malt or Munich Malt. Maillard reaction products produce entirely different flavors (toasty, bready, etc.) than caramelized sugar (caramel, sweet, etc.) Thus, non-crystal Caramel Malt contains roughly 50% hard, glassy crystal malts, and 50% crunchy, Vienna- or Munich-type malts.

The newer and common way of producing non-crystal Caramel Malt is to produce crystal malt, and then to blend in a portion of Vienna Malt and/or Munich Malt to achieve the desired characteristics. This leads to greater consistency in the final malt. Briess and Weyerman, for example, produce their non-crystal Caramel Malt in this fashion.